Blood sugar normally fluctuates throughout the day, withspikeshappening after meals.

For reference, most nondiabetic people wake up with afasting glucoselevel of 99 mg/dL or below.

Regular exercise helps lower blood sugar by increasing the muscles' need to remove glucose for energy.

High Blood Sugar Causes in People Without Diabetes - Illustration by Jessica Olah

Verywell / Jessica Olah

Elevated cortisol can interfere with insulin, leading to insulin resistance.

These cells produce insulin.

When they’re damaged, the pancreas can’t make enough insulin to regulate blood sugar effectively.

Polycystic ovary syndrome:People with PCOS often have hormonal imbalances, including elevated testosterone and insulin.

Despite high insulin levels, many people with PCOS experience insulin resistance.

As a result, excess glucose remains in the bloodstream, leading to hyperglycemia.

Physical trauma:Physical stress from injuries or burns can raise blood sugar by changing glucose metabolism.

Physical stress also triggers the release of inflammatory proteins called cytokines that promote insulin resistance.

Surgical stress:The body also undergoes stress after surgery.

Infections:Stress-induced hyperglycemia can occur with infections like pneumonia or urinary tract infections.

Elevated cortisol levels during infections block insulins ability to lower blood sugar, leading to high glucose levels.

They activate enzymes that increase glucose and disrupt insulins ability to regulate it.

Hospitalized patients receiving IV nutrition, which often contains sugar solutions, are also at risk for hyperglycemia.

These fat cells also limit the removal of glucose for energy or storage in muscles.

Gum disease is also common in people with diabetes.

Some dentists even check for warning signs of diabetes during regular oral exams.

What Causes High Blood Sugar Besides Sugar?

Sugar isnt the only factor that can lead to high blood sugar in nondiabetic individuals.

For example, a starchy bagel can cause blood sugar to rise even higher than a sugar donut.

What Does High Blood Sugar Feel Like?

When blood sugar levels are excessive, people may feel anxiety due to rapid heartbeats.

They may also have trouble concentrating or feel confused.

How Can I Flush My Blood Sugar Fast?

Drinking water can help lower blood sugar levels, but it won’t work instantly.

If your symptoms occur suddenly after you have an injury or illness, you should seek immediate care.

Excessive ketones can build up to toxic levels in the blood.

DKA requires immediate medical attention.

It is often the first sign of diabetes in people who haven’t yet been diagnosed.

If you have high blood sugar often, its important to check with your healthcare provider and monitor it.

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